Direct nitration of imipramine in acetic acid gave the 2-nitro or 2,8-dinitro derivative depending on the conditions used. These compounds were determined to function as specific, irreversible inhibitors of serotonin uptake and (3H)-imipramine binding to high affinity sites in brain and platelet, and should prove valuable in further elucidation of the mechanism of action of tricyclic antidepressants. Both enantiomers of methyl substituted phencyclidine derivative were synthesized by a route which afforded optically pure material of known absolute configuration. Phencyclidine (PCP) and these enantiomers were studied using both electrophysiological and behavioral paradigms. Stereospecificity (5-fold) was observed for the methyl derivatives. Adrenergic input appears to be involved in PCP induced changes in pyramidal neuron discharge.